Improvement in machines for grinding marble and tile



N. W. ROBINSON, FVW. SMITH & H. CAMPBELL.

Machine for Grinding Marble and Tile.

Patented April 20; 1875 Jagj 0 l 2r 4 Z f I 7 1 a I! H I 1: f I if r J Ji f, I c

THE GRAPHIC C0.PHOTO.-LITH.39 EMU PARK PLACEJLK NORMAN W. ROBINSON,FRANK W. SMITH, AND HENRY CAMPBELL, OF BURLINGTON, VERMONT.

IMPROVEMENT IN MACHINES FOR GRINDING MARBLE AND .TILE.

Specification forming part of Letters Patent No. 162,253, dated April20, 1875; application filed November 10, 1874.

To all whom it may concern:

Be it known that we, NORMAN W. ROBIN- SON, FRANK W. SMITH, and HENRYCAMP- BELL, of Burlington, in the county of Ohittenden and State ofVermont, have invented certain new and useful Improvements in Machinesfor Grinding Tile and Marble; and we do hereby declare that thefollowing is a full, clear, and exact description thereof, which willenable others skilled in the art to which. it pertains to make and usethe same, reference being had to the accompanying drawings, and to theletters of reference marked thereon, which form a part of thisspecification, and in which Figure 1 is a side elevation, and Fig. 2 aplan view, of our machine. Fig. 3 is a halfsize sectional view of theslide F, spindle I, and disk J.

Similar letters of reference indicate corresponding parts.

A represents an upright frame, which supports the uprightshaft B, onwhich is mounted the rubbing-bed G for grinding marble. To the posts Aare attached horizontal timbers D, to which is attached by bolts a thehorizontal arm E, upon which is mounted the whole machine (except thefoot-lever) for grinding mar-- ble. The arm E is adjustable by means ofthe slots b, so the machine can be moved in and out over the face of therubbing-bed, to equalize the wearing of the bed. On the outer end of theadjustable arm E is attached a suitable bearing for the slide F, whichslides up and down in its bearing for the purpose of bringing the disk Jand springs 0 down upon the marble. On the lower end of the slide F isattached by the screw-joint G a socket, H, which forms a bearing for thespindle I, and a recess, i, for the protection of the upper end or hubof the disk J and spindle I from the injurious effects of the water andsand used in grinding marble. To

the center of the disk.

more clearly in Fig. 4, are made in the form of a cross, with their endsequidistant from the center. There are blocks (1 attached to the undersides of the outer ends of the springs for holding the marble. The endsof the springs are turned down and extend below the blocks cl, whichform a hook to hold the marble in position while being ground. Thesprings and disks are secured to the spindle I by the screw 6. L is apost attached to the sliding arm E. M is a lever with one end attachedto the post. N is a connection between the lever and the slide F. O is aconnection between the lever M and the foot-lever P. Q is a springattached to the post L. R is a connection between the spring and thelever M, the spring always holding the slide and disk up from therubbing-bed when the machine is not in operation. S is a chamber in theslide F to be filled with cotton, to retain oil for oiling the spindleI.

The tile, two or four pieces, may be placed under the blocks, which areattached to the under side of the springs c; or one piece may be placeddirectly under the disk. The footlever P is pressed down, which, bymeans of the connections 0 and N with the lever M and slide F, pressesthe springs down firmly upon the marble, holding it in contact with therubbing-bed until ground to a smooth surface. The increased velocity ofthe outer portion of the bed that is in contact with the marble gives ita rapid rotary motion, the disk revolving with the spindle I, the ovalhead of the spindle sustaining the pressure in a suitable bearing, g.When the grinding is finished the-foot-lever is released, the springraises the disk up, and the marble is removed. The operation is rapidlyrepeated, thereby saving much time and expense in finishing marble, andgiving it a much smoother surface than can be obtained by any other modeof grinding.

NVhat we claim as new, and desire to secure by Letters Patent, is

1. In a stone-grinding machine, the combination of the spindle I withthe disk J and rubber disk K, and spring-arms c, substantially as andfor the purposes herein set forth.

2. The construction and arrangement of the our own, We afiix oursignatures in presence socket H, with the spindle I, disk J, and the twowitnesses.

slide F substantially as and for the purposes herein set forth. igg N wfitgn mson.

3. The combination of the adjustable arm HENRY CAMPBELL E, the slide F,post L, lever M, spring Q, and I connections 0, N, and R, substantiallyas and Witnesses: for the purposes herein set forth. D. W. ROBINSON,

In testimony that we claim theforegoingas 1 F. W. VAN SICKLEN.

